1. Field of the Invention
The present invention relates to a method of storing a substrate having an active group or a probe molecule immobilized thereon, a method of producing a microarray using the UV film, and a substrate having the UV film attached thereto.
2. Description of the Related Art
A microarray is a substrate on which specific molecules are immobilized in predetermined regions at a high density. Examples of microarrays include a polynucleotide microarray and a protein microarray. A polynucleotide microarray is a substrate on which polynucleotides are immobilized in predetermined regions at a high density. Such microarrays are well known in the art and are disclosed in, for example, U.S. Pat. Nos. 5,445,934 and 5,744,305.
Generally, microarrays are produced using photolithographic technology. In the photolithographic method, a predetermined region of a substrate coated with a monomer having a removable protective group is exposed to an energy source to remove the protective group from the monomer, and then a second monomer having a removable protective group is coupled to the monomer. The process of exposure to an energy source, removal of the protective group, and coupling of a monomer is repeated to produce a desired polynucleotide array. The polynucleotide immobilized on the microarray is synthesized by extending the monomers one by one. In a spotting method, a microarray is produced by immobilizing a previously synthesized polynucleotide at a predetermined location on a substrate. The substrate is initially coated with an active group, for example, an amino group or an aldehyde group, and the probe molecule such as a polynucleotide is immobilized on the substrate via the active group. Polynucleotide microarrays and methods of producing the same are described in U.S. Pat. Nos. 5,744,305, 5,143,854 and 5,424,186, the disclosures of which are incorporated herein in their entireties by reference.
In general, when a microarray is produced using the spotting method, the substrate coated with the active group is previously manufactured, and is stored or in the market until use. The active group coated on the substrate may react with oxygen in the atmosphere to change its reactivity or be adversely affected by moisture in the atmosphere. Thus, the substrate coated with the active group is packaged in a nitrogen-filled package, in a vacuum package, or packaged together with a desiccating agent. However, such a packaging method cannot fully protect the substrate against oxygen or moisture in the atmosphere and is complicated.
A UV film is used during the manufacture of a semiconductor chip in order to protect a surface of the semiconductor chip from silicon particles generated in a process of dicing the semiconductor chip into semiconductor chip units or from water used in the dicing process. That is, in order to protect the surface of the semiconductor chip, the UV film is attached to a semiconductor wafer, the dicing process is performed, and then the UV film is removed from the wafer. The UV film is sufficiently adhesive force to be attached to the silicon wafer at the initial time of the dicing, but the adhesiveness remarkably decreases after the UV film is exposed to UV light. The UV film is widely used when dicing objects such as semiconductor wafers, and is well known in the art. For example, dicing films described in U.S. Pat. Nos. 4,720,317, 4,913,960, and 4,968,559, the disclosures of which are incorporated herein in their entirety by reference, can be used.
The inventors of the present invention conducted research on a method of safely storing a substrate coated with an active group for a long time and discovered that when the substrate coated with the active group is stored with a UV film attached thereto, the lifetime of the substrate can be extended.